1. Field of the Invention
This invention relates generally to shoes and more particularly, to a sole which is suitable for use in an athletic shoe for use by runners, joggers and the like.
2. Description of the Prior Art
One of the problems encountered by runners, joggers, walkers and other athletes (hereinafter for brevity, referred to as runners) is the lack of a shoe and in particular, a shoe containing a sole which is designed and manufactured to meet and compensate for the problems associated with the physical act of running.
Many injuries encountered in the various activities which involve running or walking are directly attributable to the footwear worn by the runner. Examples of these injuries include tendonitis, fallen arches, damaged knees, etc. They occur primarily because the footwear worn does not compensate for the stress which is applied to various parts of the foot during the running activity, stiffness in the footwear and the lack of flexibility and stability in the sole of the footwear worn.
In those shoes which have attempted to overcome these problems, a further problem has arisen which is that these shoes wear out very quickly and must be discarded after a short period of use, thereby increasing tremendously the participatory costs of the activity incurred by the participant.
Canadian Pat. No. 377,764 issued on Nov. 15, 1938 to Arthur Fisch shows an early attempt to compensate for problems encountered by users of these types of footwear. While this patent relates particularly to "house shoes" and not directly to athletic footwear, it attempts to provide a shoe which allows for the natural rolling of the foot from heel to toe by using a series of studs or projections underneath the arch support and a plurality of arch supporting ribs and a series of web forming cells underneath the toe portions. While this structure improves the resiliency of the shoes, it does not provide sufficient support and resiliency for use by runners. Also, the shoe provides no means to prevent pronation which may occur during running or similar activities.
U.S. Pat. No. 2,090,881 granted to Wilson on Aug. 24, 1937 provides a cushioning member for use as an insole or an outsole to retain the resiliency of the shoe and to ease the pressure created when the shoe contacts the ground. A plurality of individual air-filled cells are used as the cushioning mechanism with each cell sealed.
While this shoe increases the cushioning effect of a shoe, it does not prevent pronation of the foot which is the cause of many injuries.
Similarly, the shoe disclosed in U.S. Pat. No. 2,553,616 granted to Walls on May 22, 1951 addressed itself to some of the problems encountered by runners but provides no solution to prevent rapid pronation.
These foregoing examples and other sole systems used in the prior art utilize a plurality of inclined flat layers of different material such as gums, rubbers, elastics and other synthetic materials to create an elevation of the sole of approximately one inch at the heel portion of the shoe which gradually decreases towards the toe portion of the sole.